A typical prior art ophthalmic delivery device, such as an eye dropper, includes a vial for holding the fluid to be dispensed into the eye, and a cap and eye-dropper assembly. The cap includes a squeeze bulb for drawing fluid from the vial into a hollow tube of the dropper. The user must then hold the dropper over the eye, and squeeze the bulb to release a drop of fluid into an eye. One drawback associated with such prior art ophthalmic delivery devices is that many users have found them difficult to use. Some users have difficulty delivering drops into the eyes and instead spill the drops onto other parts of the face. Other users have difficulty measuring the dosage and/or manipulating the dropper. Another drawback is that it can be difficult to maintain sufficiently precise control over the volume of each drop from one drop to the next. Yet another drawback is that such prior art devices typically cannot hold multiple doses of non-preserved medicaments.
The present inventor has recognized these and other problems associated with prior art ophthalmic delivery devices and has provided improved ophthalmic delivery devices that overcome many of the problems encountered in the prior art. For example, the present inventor has provided an ophthalmic delivery device including a body defining therein a variable volume chamber for holding a reservoir of medicament; a piston-type pump coupled in fluid communication with the variable-volume chamber for pumping metered doses of medicament therefrom; a nozzle including a one-way valve coupled in fluid communication with the pump for dispensing from the device the pumped metered dosages of medicament; an actuator for actuating the pump by, for example, depressing the actuator with a finger; and an eyelid depressor for exposing the ocular cul-de-sac upon actuating the pump and automatically delivering a precise volume of medicament to the conjunctiva cul-de-sac. One of the issues encountered with such improved ophthalmic delivery devices is that the speed of the metered dosage delivered by the pump can be greater than the speed of a drop delivered by a traditional eye dropper, i.e., one that uses gravitational force to deliver a drop from the dropper tip toward the eye. Accordingly, the energy imparted to the eye upon impact of the dosages delivered by such mechanically actuated ophthalmic delivery devices can be greater than that of traditional gravity dispensed drops.
Accordingly, it is an object of the present invention to overcome one or more of the above-described drawbacks and/or disadvantages, and to provide an improved ophthalmic delivery device and method capable of delivering metered dosages of fluids onto an eye such that the energy imparted to the eye upon impact of the dosage is less than the energy imparted by previous mechanically-actuated ophthalmic delivery devices.